Dot sighting device with large caliber

ABSTRACT

Provided is a dot sighting device with large caliber for binocular vision in which sighting can be performed rapidly and accurately by minimizing parallax. The dot sighting device is attached to and detached from a mount for a heavy machine gun. In addition, by using the dot sighting device with large caliber, a user can rapidly and accurately sight and fire a target by taking into consideration types and characteristics of the target and a distance to the target.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a reissue continuation of application Ser. No.15/194,065, which is a reissue divisional of application Ser. No.13/755,913, filed Jan. 31, 2013, which is a reissue of U.S. Pat. No.8,087,196, the entire contents of each of which are incorporated hereinin their entirety.

TECHNICAL FIELD

The present invention relates to a sighting device installed in a heavymachine gun, and more particularly, to a dot sighting device with largecaliber for binocular vision.

BACKGROUND ART

Characteristics of a rifle or heavy machine gun are determined accordingto whether the user wants to rapidly sight and fire and whether the userwants to accurately sight a target. In general, rifles or heavy machineguns sight a target by aligning a line of sight of a rear sight and afront sight. The sighting performed by the aligning of the line of sightof the front sight positioned at an end of a gun barrel and the rearsight positioned at an upper portion of a gun body allows the user toaccurately fire according to their ability.

However, when the sighting is performed using both the rear sight andthe front sight, it is difficult to align the line of sight due to evensmall vibrations or tremors, and it is difficult to rapidly sight atarget at a short distance or in an urgent situation.

That is, in such situations, complicated processes, such as capture andconfirmation of a target, alignment of a line of sight, sighting, etc.,and time are required. In addition, since the front sight and the rearsight are themselves very small, they are sensitive to even smallvibrations when the front sight and the rear sight are accuratelyaligned. Moreover, when a user excessively concentrates on the alignmentof the line of sight, the user s sight is focused on the front sight andthe rear sight rather than the target or front circumstances. Thus, theuser focuses too much attention on the alignment of the line of sight tothe detriment of other duties such as firing or coping with urgentsituations.

Accordingly, to cope with the difficulty in the alignment of the line ofsight and raise the accuracy of sighting, a sighting device equippedwith a telephoto lens has been proposed. However, an optical sightingdevice equipped with a telephoto lens is sensitive to even smallvibrations when magnification increases due to the use of the telephotolens. Thus, there is still a difficulty in rapid sighting.

To address these problems, a dot sighting device in which a nomagnification or low magnification lens is used in an optical sightingdevice, and an aiming point only is simply used without a complicatedline of sight has been proposed.

Optical dot sighting devices with no magnification (low magnification)can simply and rapidly sight a target, and are very useful in urgentsituations or for short distances. In particular, time spent inalignment of the line of sight can be saved, sighting is itselfperformed such that a dot image is positioned to coincide with a target,and thus the user does not have to devote all of their attention to thealignment of the line of sight. Ultimately, rapid and accurate sightingare possible, and attention can be focused on other urgent situations.

However, conventional dot sighting devices are devices for monocularvision in which a user has to watch a sight mirror with only one eye.Thus, it takes a long time to sight a target, and visual problems alsooccur.

FIG. 1 is a schematic cross-sectional view of a conventional dotsighting device 1 for monocular vision. Referring to FIG. 1, in theconventional dot sighting device 1, the inside of the dot sightingdevice 1 is aligned using a rifle barrel alignment terminal 3 through afixed grille 11, and then light emitted from a LED light source 5 isreflected from a reflection mirror 7, whereby an observer confirms anobject with one eye. In general, a front surface (inside of the sightingdevice) of the reflection mirror 7 is coated in order to reflect thelight emitted from the LED light source 5, and curved surfaces of thefront surface and a rear surface of the reflection mirror 7 arespherical, and have the same curvature.

A dot image reflected from the reflection mirror 7 is sighted tocoincide with a target object viewed through a protective window 9 at nomagnification, whereby a user fires at the target object when the dotimage reflected from the reflection mirror 7 coincides with the targetobject. Thus, the sighting can be easily performed.

More particularly, the light irradiated from the LED light source 5disposed in the dot sighting device 1 is reflected from the reflectionmirror 7, and incident on the eye of an observer in parallel. Thedirection in which the parallel light is reflected should coincide witha bullet firing axis of a gun barrel. If the parallel degree of the dotsighting device 1 does not coincide with the bullet firing axis of thegun barrel, a user cannot hit the target object even when a dot of thelight irradiated from the LED light source 5 coincides with the targetobject. Thus, to coincide the parallel degree of the dot sighting device1 with the bullet firing axis of the gun barrel, the rifle barrelalignment terminal 3 having vertical and horizontal adjustment functionsis operated to coincide an optical axis of an inner barrel with thebullet firing axis of the gun barrel.

FIG. 2 is a schematic view illustrating the case in which parallaxoccurs in the conventional dot sighting device of FIG. 1. However, asillustrated in FIG. 2, if the width of the reflection mirror 7 is notgreater than a distance between pupils of a user, binocular visionobtained by overlapping of both eyes does not exist. In this state, whenan external object is viewed through the reflection mirror 7, it isimpossible to obtain information on the external object by binocularvision. Thus, the external object is viewed by an eye superior to theother eye, or double vision of the object occurs. In this case, eyestrain is caused by not being able to accurately obtain information onthe external object.

To address this problem, if only the size of a sight mirror, i.e., aprotective mirror and the reflection mirror is simply increased, asillustrated in FIG. 2, parallax of the reflection mirror 7 itself occursdue to an increase of aberration of an ambient portion of the reflectionmirror 7. Thus, the parallel degree of the dot sighting device does notcoincide with the bullet firing axis of the gun barrel. The occurrenceof parallax reduces the accuracy of sighting the target. FIG. 2illustrates parallax in which light rays reflected from a generalspherical reflection surface are not parallel to each other.

In addition, in conventional dot sighting devices, as illustrated inFIG. 1, regardless of the distance to the target, light irradiated fromthe LED light source 5 along the same optical axis is reflected from thereflection mirror 7, whereby a dot image is focused on the target.However, gravity continuously acts on a bullet after the bullet is fireduntil it hits the target, and thus the farther away the target, thegreater a path of the bullet is changed. In conventional dot sightingdevices, to reflect the change in the path of the bullet according tothe distance, an optical axis of a main body of the dot sighting deviceand the parallel degree of the bullet firing axis of the gun barrel aremechanically adjusted. Thus, when the distance to the target material issuddenly changed, users cannot rapidly cope with the situation.

Moreover, the light irradiated from the LED light source uses a singlereticle, and thus the same dot with respect to all targets is alwaysformed. However, targets of a heavy machine gun, such as human, tanks,and aircraft each have different characteristics. For example, in thecase of firing at aircraft, sighting and firing should be performedtaking into consideration the velocity of the aircraft. Thus, in aconventional dot sighting device, it is difficult to perform accuratesighting and firing taking into account characteristics of targets.

DISCLOSURE OF INVENTION Technical Problem

The present invention provides a dot sighting device with large caliberin which binocular vision is possible.

The present invention also provides a dot sighting device with largecaliber that can prevent occurrence of parallax through a reflectionmirror.

The present invention also provides a dot sighting device that can sighta target rapidly, taking into account a change of a bullet pathaccording to a distance to the target.

The present invention also provides a dot sighting device that canrapidly sight a target by using a dot image that uses a reticlecorresponding to characteristics of the target according to the target.

In addition, the technical goal of the present invention is not limitedthereto, and the present invention can be embodied with a variety ofgoals by one of ordinary skill in the art to which the present inventionpertains within the claims of the present invention.

Technical Solution

According to an aspect of the present invention, there is provided a dotsighting device comprising: a reflection mirror; an illumination havinga LED irradiating light to the reflection mirror and a transparentreticle that is positioned in front of the LED and forms a dot image bytransmitting the light irradiated from the LED; and a fixed grilleformed on a lower portion of the dot sighting device, wherein the dotsighting device is attached to and detached from a mount for a heavymachine gun by the fixed grille, and a width X of the reflection mirroris greater than a distance Y between both eyes of a user.

The dot sighting device may further comprise a reticle selection unitconnected to the illumination unit, wherein the transparent reticle isformed on a plane perpendicular to a reticle rotation axis that extendsfrom the reticle selection unit and penetrates the illumination unit,thus being able to rotate based on the reticle rotation axis by rotationof the reticle selection unit, and a plurality of reticles according toa target are formed on the transparent reticle on the same radial axisaround the reticle rotation axis, and one of the reticles correspondingto the target is selected by rotating the reticle selection unitaccording to the target.

The dot sighting device may further comprise a reticle selection unitconnected to the illumination unit, wherein the transparent reticle isformed on a plane perpendicular to a reticle rotation axis that extendsfrom the reticle selection unit and penetrates the illumination unit,thus being able to rotate based on the reticle rotation axis by rotationof the reticle selection unit, and a plurality of reticles are formed onthe transparent reticle on the same radius axis around the reticlerotation axis, wherein the reticles are formed closer to the reticlerotation axis as a distance to the corresponding point of impact isfarther, and one of the reticles is selected by rotating the reticlerotation unit according to a distance to the target.

The reticle rotation axis may comprise, around a reticle rotationconnection axis, a rotation axis on an illumination unit side having aconvex-concave portion with a plurality of convexes-concavescorresponding to a distance to a point of impact; and a rotation axis ona reticle selection unit side that has protrusions coupled to desiredconvexes-concaves of the convex-concave portion on an end thereof andthe other end of which is connected to the transparent reticle, whereinthe rotation axis on the illumination unit side and the rotation axis onthe reticle selection unit side are separated from each other by pullingthe reticle selection unit, and then the reticle selection unit isrotated so as to couple a desired convex-concave corresponding to thedistance to the point of impact of the convex-concave portion of therotation axis on the illumination unit side with the protrusion of therotation axis on the reticle selection unit side.

The dot sighting device may comprise an upper plate and a lower plate,wherein the upper plate comprises a protective window; a reflectionmirror; and an illumination unit, and wherein the lower plate comprises:a fixed grille formed on a lower portion of the dot sighting device; abullet path adjustment handle installed at a side surface of the dotsighting device; an upper/lower click control bolt that connects theupper and lower plates and sets an origin point; a bullet pathadjustment body that is accommodated in a bullet path adjustment bodyaccommodation unit formed in the lower plate and is connected to theupper plate by fixing an end on the lower plate side of the upper/lowerclick control bolt to an upper portion of an upper/lower plateconnection rotation axis penetrating a side surface of the lower plate;a bullet path adjustment axis that comprises a bullet path adjustmentportion positioned on a bullet path adjustment axis contact portion atan end of the bullet path adjustment body, and penetrates the lowerplate, thereby being connected to the bullet path adjustment handle; aconnection pin of the bullet path adjustment body and the lower plate,penetrating the other end of the bullet path adjustment body and thelower plate from a side surface of the lower plate, thereby connectingthe bullet path adjustment body and the lower plate; and a springaccommodation portion formed in a top surface of the lower plate on thebullet path adjustment axis contact portion side based on the connectionpin, wherein the spring accommodation portion accommodates a spring,thereby pushing the upper plate and the lower plate apart from eachother, wherein the bullet path adjustment body is rotatable around theupper/lower plate connection rotation axis, wherein the bullet pathadjustment axis contacts a top surface of the bullet path adjustmentaxis contact portion of the bullet path adjustment body, and comprises abullet path adjustment portion having a plurality of contact surfaceseach having a different normal distance from the center of the bulletpath adjustment axis, corresponding to a distance to a target, wherein,in the bullet path adjustment portion, by rotating the bullet pathadjustment handle, a contact surface corresponding to a distance to adesired target contacts the bullet path adjustment axis contact portion.

The reflection mirror may comprise a doublet, each of a first surfaceand a third surface of the reflection mirror is spherical, and a secondsurface of the reflection mirror comprises a LED reflection surface,wherein a radius curvature of the first and third surfaces satisfies thefollowing equation:

$\begin{matrix}{{D_{1} = \frac{n - 1}{R_{1}}},{D_{2} = \frac{1 - n}{R_{3}}}} & (1) \\{{D_{1} + D_{2} - {\frac{d}{n}D_{1}D_{2}}} = 0} & \;\end{matrix}$

wherein D₁ denotes a refractive power of the first surface, D₂ denotes arefractive power of the third surface, d denotes a distance between thecenters of the first and third surfaces, R₁ denotes a radius curvatureof the first surface, R₃ denotes a radius curvature of the thirdsurface, and n denotes a refractive index of the material.

The second surface may comprise an aspheric surface having a coniccoefficient.

Advantageous Effects

According to the present invention, a dot sighting device with largecaliber for a heavy machine gun in which binocular vision is possiblecan be obtained.

In addition, according to the present invention, a target can be rapidlysighted taking into consideration distance amendment, and thus firingcan be performed taking into consideration differences according to adistance of the target.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it will be understoodby those of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the spirit and scopeof the present invention as defined by the following claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present inventionwill become more apparent by describing in detail exemplary embodimentsthereof with reference to the attached drawings in which:

FIG. 1 is a schematic cross-sectional view of a conventional dotsighting device for monocular vision;

FIG. 2 is a schematic view illustrating the case in which parallaxoccurs in the conventional dot sighting device of FIG. 1;

FIG. 3 schematically illustrates a visual problem occurring when aconventional dot sighting device for monocular vision is observed withboth eyes;

FIG. 4 is a schematic view showing a case when a dot sighting devicewith large caliber for binocular vision, according to an embodiment ofthe present invention, is observed with both eyes;

FIGS. 5 and 6 are schematic views illustrating a dot sighting deviceequipped with a reticle selection unit, according to an embodiment ofthe present invention;

FIG. 7 is a schematic cross-sectional view for explaining an operatingprinciple of a dot sighting device according to an embodiment of thepresent invention;

FIG. 8 is a schematic cross-sectional view of an illumination unitaccording to an embodiment of the present invention;

FIG. 9 is a schematic view of a revolving transparent reticle accordingto an embodiment of the present invention;

FIG. 10 is a view of a revolving transparent reticle according toanother embodiment of the present invention;

FIG. 11 is a schematic view of a reticle rotation axis according to anembodiment of the present invention;

FIGS. 12 and 13 are schematic views of a dot sighting device with largecaliber according to another embodiment of the present invention, inwhich an optical axis adjustment device is included;

FIG. 14 is a schematic assembly view of an optical axis adjustmentdevice according to an embodiment of the present invention;

FIGS. 15 and 16 are schematic views for explaining an operatingprinciple of a bullet path adjustment body and a bullet path adjustmentaxis of the optical axis adjustment device of FIG. 14, according to anembodiment of the present invention:

FIG. 17 is a schematic view illustrating a structure of a reflectionmirror according to an embodiment of the present invention; and

FIG. 18 is a schematic view illustrating a structure of a reflectionmirror according to another embodiment of the present invention.

FIG. 19 illustrates a graph showing Tangential ray aberration degrees ina specific case.

FIG. 20 illustrates another graph showing Tangential ray aberrationdegrees in another specific case.

FIG. 21 illustrates yet a further graph showing Tangential rayaberration degrees in yet a further specific case.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will now be described more specifically withreference to the accompanying drawings, in which exemplary embodimentsof the invention are shown.

FIG. 3 illustrates a visual problem occurring when a reflection mirror15 of a conventional dot sighting device is observed with both eyes 13.Referring to FIG. 3, when a width X of the reflection mirror 15 is thesame as or less than a distance Y between both eyes 13, diplopia asdescribed above occurs, thereby causing eye strain, and externalinformation acquired by both eyes 13 is distorted.

FIG. 4 is a schematic view showing a case when a dot sighting devicewith large caliber for binocular vision, according to an embodiment ofthe present invention, is observed with both eyes 13. Referring to FIG.4, a width X of a reflection mirror 16 is greater than a distance Ybetween both eyes 13. Thus, a right eye view ‘A’ nearly coincides with aleft eye view ‘B’ and external information is acquired in an overlappedregion of the right eye view ‘A’ and the left eye view ‘B’. That is,since information on external objects is acquired by simultaneouslyusing both eyes 13, stereoscopic vision, which is an advantage ofbinocular vision with respect to monocular vision, is possible, and asense of distance can be maintained.

Hereinafter, various embodiments of the dot sighting device with largecaliber, according to the present invention, will be described withreference to the accompanying drawings. However, these embodiments arefor illustrative purposes only and are not intended to limit the scopeof the present invention. In addition, simple replacements, such asdesign modifications obvious in the art to which the present inventionpertains are not intended to limit the scope of the present invention.

Embodiment 1

FIGS. 5 and 6 are schematic views illustrating a dot sighting device 2equipped with a reticle selection unit, according to an embodiment ofthe present invention.

In the dot sighting device 2, a fixed grille 23 (refer to FIG. 13) isfixed to a mount for a heavy machine gun (not shown) with fixing bolts25, and a an upper/lower click control bolt 17 and a left/right clickcontrol bolt 45 (refer to FIG. 13) are used to adjust an origin point azero point (or set zero). A user confirms an external target through aprotective window 27 and a reflection mirror 16. Light irradiated froman LED light source in an illumination unit 19 forms a dot image on thereflection mirror 16 and is reflected, and the reflected light isincident on eyes of a user, thereby allowing the user to view the dotimage. The brightness of the LED light source can be adjusted by acontrol switch 31. In addition, the LED light source can be driven by abuilt-in battery in a battery case 29, or driven with electrical powersupplied from an external electrical source. Alternatively, the built-inbattery can be charged using an external electrical source.

FIG. 7 is a schematic view for explaining an operating principle of anillumination unit 19 and a reflection mirror 16 of a dot sighting deviceaccording to an embodiment of the present invention.

Referring to FIG. 7, an illumination device 33 using an LED or the likeis installed in the illumination unit 19, and acts as a light source.Light irradiated from the illumination device 33 is transmitted througha transparent reticle of a revolving transparent reticle 35 disposed infront of the illumination device 33 and is irradiated to the reflectionmirror 16. The light irradiated to the reflection mirror 16 is reflectedand incident on eyes of a user, and the user views a transparentreticle-shaped dot.

FIG. 8 is a view illustrating in detail an operating principle of areticle selection unit 21 and the illumination unit 19 of the dotsighting device of FIG. 7, according to an embodiment of the presentinvention. The revolving transparent reticle 35 is formed on a planeperpendicular to a reticle rotation axis 37 that extends from thereticle selection unit 21 disposed adjacent to the illumination unit 19and penetrates the illumination unit 19. In addition, when the reticlerotation axis 37 rotates by rotation of the reticle selection unit 21,the revolving transparent reticle 35 accordingly rotates. Thus, userscan select a desired reticle from among various types of reticles formedin the revolving transparent reticle 35 by rotating the reticleselection unit 21.

Example 1

FIG. 9 is a view of the revolving transparent reticle 35 of the dotsighting device of FIG. 7, according to an embodiment of the presentinvention. A variety of reticles 39A through 39F are formed in therevolving transparent reticle 35 along a reticle rotation line 40 havinga radial axis based on a center axis 37′ of the revolving transparentreticle 35. For example, to sight and fire at a moving vehicle,helicopter, fighter plane, or the like, the sighting should be performedby taking into consideration velocity or the like of the moving target,unlike firing at human. Thus, a dot image should be formed by takingsuch factors into account. Dot images for objects are, in general,largely categorized into dot images for short distances, dot images forlong distances, and dot images for anti-aircraft firing. In addition,different dot images are used for humans and horses, for tanks, forhelicopters, for fighter planes, and the like. In the revolvingtransparent reticle 35 according to the current embodiment of thepresent invention, taking into consideration the characteristics of thetarget, a long distance reticle for humans and horses 39A, a shortdistance reticle for humans and horses 39B, a reticle for still vehiclesand tanks 39C, a reticle for moving vehicles and tanks 39D, a reticlefor anti-aircraft helicopters 39E, and a reticle for anti-aircraftfighter planes 39F are radially formed along the reticle rotation line40.

The reticle rotation axis 37 penetrates the center axis 37′ of therevolving transparent reticle 35, and the revolving transparent reticle35 is fixed to the reticle rotation axis 37 and rotates according to therotation of the reticle rotation axis 37. Thus, users can rapidly selecta reticle for forming a dot image appropriate for a target by rotatingthe reticle selection unit 21. As a result, sighting and firing can berapidly and accurately performed.

Example 2

FIG. 10 is a view of the revolving transparent reticle 35 of the dotsighting device of FIG. 7, according to another embodiment of thepresent invention. A fired bullet is continuously affected by gravityuntil the bullet reaches a target. Thus, if a distance to the targetmaterial is farther, the bullet reaches a position that is differentfrom an originally sighted position. Therefore, to increase accuracy,the distance to the target should be amended while sighting the target,taking into consideration the distance.

When gravity is taken into consideration, the farther the distance tothe target, the greater an angle formed between a gun barrel and ahorizontal plane should be. Thus, in the revolving transparent reticle35 of FIG. 10, taking the above into consideration, the farther thedistance to the target based on a sighting baseline 41, the closerreticles 39′A through 39′F are formed to the center axis 37′.

For example, if the sighting baseline 41 is a baseline with respect to atarget 100 m away, the reticle 39′A with respect to the target 100 maway from a shooter is formed on the sighting baseline 41. In addition,the reticle 39′B with respect to a target 200 m away from the shooter isformed towards the center axis 37′ as much as pre-set distance from thesighting baseline 41. In addition, the reticle 39′C with respect to atarget 400 m away, the reticle 39′D with respect to a target 800 m away,the reticle 39E with respect to a target 1200 m away, and the reticle39′F with respect to a target 1600 m away are formed towards the centeraxis 37′ as much as pre-set distances.

The reticle rotation axis 37 penetrates the center axis 37′ of therevolving transparent reticle 35, and the revolving transparent reticle35 is fixed to the reticle rotation axis 37 and rotates according to therotation of the reticle rotation axis 37. Thus, users can rapidly selecta reticle for forming a dot image appropriate for a target by rotatingthe reticle selection unit 21, taking into consideration a distance tothe target. As a result, sighting and firing can be rapidly andaccurately performed.

In Examples 1 and 2, the center axis 37′ of the revolving transparentreticle 35 is formed at the center of the revolving transparent reticle35. However, the center axis 37′ can be formed at a position deviatedfrom the center of the revolving transparent reticle 35 in the twoexamples described above. That is, taking into account the distance tothe target, the center axis 37′ can be formed at a position that isclose to a reticle to be used for a long distance target in advance.

MODE FOR THE INVENTION Embodiment 2

To maintain stereoscopic vision, i.e., a sense of distance by making thewidth of a reflection mirror greater than a distance between both eyesof a user, a virtual image of a dot should be formed within binocularfixation distance. As a result, a target and a dot sighted at the targetcan be accurately viewed without eye strain.

To form a dot at a binocular fixation point during binocular fixation,i.e., to position an image of a reticle by the reflection mirror at thebinocular fixation point, a change of position should be performed bymoving an illumination unit, particularly, a reticle acting as a pointlight source, forward or backward.

For example, in three cases of a 100 m reticle, a 200 m reticle, and a400 m reticle, an operation in which a position of the point lightsource of the illumination unit is finely moved to a direction of afocal point of the reflection mirror is needed.

A distance of stereoscopic vision in which human eyes can have athree-dimensional effect is about 240 m according to Hermann vonHelmholtz. Thus, 800 m, 1200 m and 1600 m reticles may be positioned atthe focal point of the reflection mirror in order to position a dotimage after reflection from the reflection mirror at infinity in frontof the eyes, as in the case of the 400 m reticle.

When the focal point of the reflection mirror is f mm, a shift s of a zm reticle from the focal point of the reflection mirror to thereflection mirror can be calculated using Equation 2 below, and examplesof the calculation are shown in the following table.

$\begin{matrix}{S = {f - \frac{1000\;{zf}}{{1000\; z} - f}}} & (2)\end{matrix}$

TABLE 1 50 m 100 m 200 m 400 m Reticle type reticle reticle reticlereticle Calculation example of a 1.05 mm 0.53 mm 0.26 mm 0.13 mm shiftof a reticle in a re- flection mirror having an actual focal distance of229 mm *The above table shows calculation of shifts of 4 types ofreticles from the focal point of the reflection mirror to the reflectionmirror in the reflection mirror having an actual focal distance of 229mm

To move the reticle taking into account the shift, a reticle rotationaxis 37 as illustrated in FIG. 11 can be taken into consideration. FIG.11 is a schematic view of the reticle rotation axis 37 illustrated inFIG. 8, according to an embodiment of the present invention.

Referring to FIG. 11, the reticle rotation axis 37 includes a rotationaxis 65 on an illumination unit side, which extends from a front surfaceof the illumination unit 19, a rotation axis 67 on a reticle selectionunit side, and a connection axis 58 of the reticle rotation axis 37. Arevolving transparent reticle is attached to a rear portion of therotation axis 67 on the reticle selection unit side. Referring to FIG.11, convexes-concaves 61a through 61c are formed on an end of therotation axis 65 on the illumination unit side along the circumferencethereof. The size of each of the convexes-concaves 61a through 61ccorresponds to a shift distance according to each of the reticles shownin the table above. Protrusions 63 are formed on an end of the rotationaxis 67 on the reticle selection unit side coupled to the rotation axis65 on the illumination unit side.

When a user pulls the reticle selection unit 21, the rotation axis 65 onthe illumination unit side and the rotation axis 67 on the reticleselection unit side are separated from each other, and the protrusions63 rotate as the rotation axis 67 on the reticle selection unit siderotates by rotating the reticle selection unit 21. When the protrusions63 are positioned to correspond to the convexes-concaves 61, whichcorresponds to a desired shift distance of the reticle, the protrusions63 and the convexes-concaves 61 are coupled if the reticle selectionunit 21 is released.

Thus, a user can rapidly amend a dot image corresponding to a distanceduring stereoscopic vision. As a result, sighting and firing can berapidly and accurately performed.

Embodiment 3

FIGS. 12 and 13 are views of dot sighting devices according to otherembodiments of the present invention, in which a path of a bullet can beadjusted.

In the present embodiments, the path of the bullet is adjusted byrotating a bullet path adjustment handle 43 instead of using the reticleselection unit. The dot sighting devices according to the currentembodiments of the present invention in which the path of the bullet canbe adjusted will now be described with reference to the followingdrawings.

FIG. 14 is a schematic assembly view of an optical axis adjustmentdevice according to an embodiment of the present invention.

A lower plate 6 illustrated in FIG. 14 is disposed below an upper plate4 of FIGS. 12 and 13.

Referring to FIG. 14, a groove in which an upper/lower click controlbolt 17 is accommodated is formed in a top surface portion of a bulletpath adjustment body 47, and an upper/lower plate connection rotationaxis 49 is inserted through a side surface center portion of the bulletpath adjustment body 47. The upper/lower click control bolt 17accommodated from the top surface portion of the bullet path adjustmentbody 47 is fixedly inserted in a center portion groove of theupper/lower plate connection rotation axis 49. The bullet pathadjustment body 47 connected to the upper/lower click control bolt 17 bythe upper/lower plate connection rotation axis 49 is accommodated in abullet path adjustment body accommodation unit 55 formed in the lowerplate 6. In addition, the bullet path adjustment body 47 is coupled tothe lower plate 6 by a connection pin 59 that penetrates a side surfaceof the lower plate 6 and couples the bullet path adjustment body 47 withthe lower plate 6.

Thus, the upper/lower click control bolt 17 can rotate around on (orscrew on) the upper/lower plate connection rotation axis 49, and thebullet path adjustment body 47 can rotate around on the connection pin59.

In addition, the bullet path adjustment body 47 is connected to theupper plate 4 through the upper/lower click control bolt 17 fixed to theupper plate 4, and is connected to the lower plate 6 by the connectionpin 59.

A bullet path adjustment axis 51 passes through the lower plate 6,passes by and contacts a bullet path adjustment axis contact portion 48of the bullet path adjustment body 47, and is connected to the bulletpath adjustment handle 43. A bullet path adjustment portion 53 of thebullet path adjustment axis 51 contacts the bullet path adjustment axiscontact portion 48 of the bullet path adjustment body 47, facing eachother.

Spring accommodation portions 57 are formed in a top surface of thelower plate 6, at a position adjacent to the bullet path adjustment bodyaccommodation unit 55 and parallel to the connection pin 59, asillustrated in FIG. 14. In addition, springs are accommodated in thespring accommodation portions 57, whereby a repulsive force acts on theupper and lower plates 4 and 6.

A configuration for adjusting the bullet path of the dot sighting deviceaccording to the present embodiment will now be described with referenceto FIGS. 15 and 16.

FIGS. 15 and 16 are schematic views for explaining an operatingprinciple of a bullet path adjustment body and a bullet path adjustmentaxis of the optical axis adjustment device of FIG. 14, according to anembodiment of the present invention.

Referring to FIG. 15, the bullet path adjustment portion 53 of thebullet path adjustment axis 51 passes by and contacts the bullet pathadjustment axis contact portion 48 of the bullet path adjustment body47. FIG. 16 is a cross-sectional view taken along a line A-B of FIG. 15.Referring to FIG. 16, the bullet path adjustment portion 53 comprises aplurality of contact surfaces 53a through 53e each having a differentnormal distance from center of rotation 60 of the bullet path adjustmentaxis 51.

The springs of the spring accommodation portions 57 push the upper andlower plates 4 and 6 away from each other, and thus a force, directedtowards the upper plate 4 from the lower plate 6 acts on the bullet pathadjustment body 47 connected to the upper plate 4 by the upper/lowerclick control bolt 17. That is, a force that rotates towards causes theupper plate 4 based to rotate upward centering on the connection pin 59continuously acts on the bullet path adjustment body 47 connected to theupper plate 4. Thus, when the contact surface contacting the bullet pathadjustment axis contact portion 48 in the bullet path adjustment portion53 is changed, a distance between the upper plate 4 and the lower plate6 is changed.

For example, when the bullet path adjustment axis contact portion 48 ofthe bullet path adjustment body 47 contacts the contact surface 53dhaving a relatively long normal distance from the center of rotation 60,and then contacts the contact surface 53a having a relatively shortnormal distance from the center of rotation 60, the distance between theupper plate 4 and the lower plate 6 becomes closer. In the oppositecase, the distance between the upper plate 4 and the lower plate 6becomes farther.

Since the lower plate 6 is fixed to the mount for a heavy machine gun,the distance between the upper plate 4 and the lower plate 6 is changedby a fine change in a slope of the upper plate 4 with respect to thefixed lower plate 6. By calculating an amendment a corrective angleaccording to a distance in advance, each of the contact surfaces 53athrough 53e of the bullet path adjustment portion 53 is formed at anormal distance corresponding to the amendment corrective angle. Thus,when a corresponding contact surface is selected by rotating the bulletpath adjustment handle 43, the slope of the upper plate 4 is changedaccording to the distance to the target. Then, when the target issighted through the reflection mirror of the upper plate 4 having thechanged slope and the protective window, the same amendment correctiveeffect according to a distance as in Example 2 of Embodiment 1 can beobtained.

Embodiment 4

As described above, in the dot sighting device having large caliber andusing the reflection mirror, according to the present invention, thereis a need to address the problem of parallax according to aberration.

FIG. 17 is a schematic view illustrating a structure of a reflectionmirror according to an embodiment of the present invention. In thepresent embodiment, a distance between a LED and a reflection surface isset at 200 mm, and a thickness of the center of the reflection mirror isset at 4.0 mm.

A LED dot is reflected from a R₂ surface and emitted to the outside. Inthis regard, when incident on the reflection mirror, the LED dot istransmitted through a R₁ surface, is reflected from the R₂ surface, andthen is transmitted through the R₁ surface again, and consequently, theLED dot is incident on the eyes of an observer. That is, since the LEDdot is transmitted through the R₁ surface twice and is transmittedthrough the R₂ surface once, a further degree of freedom in design isprovided. Due to this, parallax can be minimized. To decreasemagnification occurrence when an external target point is focused on theeyes of the observer, the reflection mirror can be configured to becomean afocal system. The configuration applies to radius curvature of firstand third surfaces by using Equation 1 below.

When d denotes a distance between centers (center thickness) of firstand third surfaces of a doublet, R₁ denotes radius curvature of thefirst surface, R₃ denotes radius curvature of the third surface, and ndenotes a refractive index of the material, the following equation isobtained.

$\begin{matrix}{{D_{1} = \frac{n - 1}{R_{1}}},{D_{2} = \frac{1 - n}{R_{3}}}} & (1) \\{{{D_{1} + D_{2} - {\frac{d}{n}D_{1}D_{2}}} = 0},} & \;\end{matrix}$

wherein D₁ denotes a refractive power of the first surface and D₂denotes a refractive power of the third surface. By using the reflectionmirror according the present embodiment, it was confirmed that parallaxwas reduced by 80% or greater.

FIG. 18 is a schematic view illustrating a structure of a reflectionmirror, according to another embodiment of the present invention.Referring to FIG. 18, when a second surface is an aspheric surfacehaving a conic coefficient, the parallax is further minimized. In thiscase, parallax was reduced by 90% or greater, compared to that of thereflection mirror of FIG. 17.

The following three graphs FIGS. 19, 20 and 21 respectively showTangential ray aberration degrees in the case of a conventional singlereflection surface, in the case of a doublet reflection surface (whenthe reflection surface between two lenses is spherical), and in the caseof a doublet reflection surface where a conic aspheric surface isadopted as the reflection surface between two lenses. Each lens has aninclination angle of −2.0°.

FIG. 19 is a graph representing spherical aberration, and when itcoincides with an X axis, parallax does not occur. A maximum aberrationvalue of the conventional single reflection surface is 0.02 mm, amaximum aberration value when the spherical reflection surface isadopted as a median surface of the doublet is 0.004 mm, and a maximumaberration value when the conic aspheric reflection surface is adoptedas a median surface of the doublet is 0.0004 mm. Thus, when a spaceaccounting for 50% of a total region from the center is regarded as aneffective space, the spherical reflection surface employed as the mediansurface of the doublet has an improvement in terms of the integral valueof spherical aberration amount (y axis) with respect to x axis (aneffective space that LED light beam reflects by a minimum of 80% orgreater, compared with the conventional single reflection surface. Inaddition, the conic aspheric reflection surface employed as the mediansurface of the doublet has an improvement in terms of the integral valueof by a minimum of 90% or greater, compared with the sphericalreflection surface employed as the median surface of the doublet.

INDUSTRIAL APPLICABILITY

According to the present invention, a dot sighting device with largecaliber for a heavy machine gun in which binocular vision is possiblecan be obtained.

In addition, according to the present invention, a target can be rapidlysighted taking into consideration distance amendment, and thus firingcan be performed taking into consideration differences according to adistance of the target.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it will be understoodby those of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the spirit and scopeof the present invention as defined by the following claims.

The invention claimed is:
 1. A dot sighting device comprising: areflection mirror; an illumination having a LED irradiating light to thereflection mirror and a transparent reticle that is positioned in frontof the LED and forms a dot image by transmitting the light irradiatedfrom the LED; a fixed grille formed on a lower portion of the dotsighting device; wherein the dot sighting device is attached to anddetached from a mount for a heavy machine gun by the fixed grille:wherein the reflection mirror comprises a doublet, with a first surface,an interior second surface and a third surface, with the first surfaceand third surface being spherical, wherein the interior second surfaceof the reflection mirror comprises a LED reflection surface; wherein aradius curvature of the first and third surfaces satisfies the followingequation: $\begin{matrix}{{D_{1} = \frac{n - 1}{R_{1}}},{D_{2} = \frac{1 - n}{R_{3}}}} & (1) \\{{D_{1} + D_{2} - {\frac{d}{n}D_{1}D_{2}}} = 0} & \;\end{matrix}$ wherein D₁ denotes a refractive power of the first surfaceD₂ denotes a refractive power of the third surface, d denotes a distancebetween the centers of the first and third surfaces, R₁ denotes a radiuscurvature of the first surface, R₃ denotes a radius curvature of thethird surface, and n denotes a refractive index of the material.
 2. Thedot sighting device of claim 1, further comprising a reticle selectionunit connected to the illumination unit, wherein the transparent reticleis formed on a plane perpendicular to a reticle rotation axis thatextends from the reticle selection unit and penetrates the illuminationunit, thus being able to rotate based on the reticle rotation axis byrotation of the reticle selection unit, and a plurality of reticlesaccording to a target are formed on the transparent reticle on the sameradial axis around the reticle rotation axis, and one of the reticlescorresponding to the target is selected by rotating the reticleselection unit according to the target.
 3. The dot sighting device ofclaim 1, further comprising a reticle selection unit connected to theillumination unit, wherein the transparent reticle is formed on a planeperpendicular to a reticle rotation axis that extends from the reticleselection unit and penetrates the illumination unit, thus being able torotate based on the reticle rotation axis by rotation of the reticleselection unit, and a plurality of reticles are formed on thetransparent reticle on the same radius axis around the reticle rotationaxis, wherein the reticles are formed closer to the reticle rotationaxis as a distance to the corresponding point of impact is farther, andone of the reticles is selected by rotating the reticle rotation unitaccording to a distance to the target.
 4. A dot sighting devicecomprising: a reflection mirror; an illumination having a LEDirradiating light to the reflection mirror and a transparent reticlethat is positioned in front of the LED and forms a dot image bytransmitting the light irradiated from the LED; a fixed grille formed ona lower portion of the dot sighting device; wherein the dot sightingdevice is attached to and detached from a mount for a heavy machine gunby the fixed grille; the dot sighting device further comprising areticle selection unit connected to the illumination unit, wherein thetransparent reticle is formed on a plane perpendicular to a reticlerotation axis that extends from the reticle selection unit andpenetrates the illumination unit, thus being able to rotate based on thereticle rotation axis by rotation of the reticle selection unit, and aplurality of reticles according to a target are formed on thetransparent reticle on the same radial axis around the reticle rotationaxis, and one of the reticles corresponding to the target is selected byrotating the reticle selection unit according to the target; wherein thereticle rotation axis comprises, around a reticle rotation connectionaxis, a rotation axis on an illumination unit side having aconvex-concave portion with a plurality of convexes-concavescorresponding to a distance to a point of impact; and a rotation axis ona reticle selection unit side that has protrusions coupled to desiredconvexes-concaves of the convex-concave portion on an end thereof andthe other end of which is connected to the transparent reticle, whereinthe rotation axis on the illumination unit side and the rotation axis onthe reticle selection unit side are separated from each other by pullingthe reticle selection unit, and then the reticle selection unit isrotated so as to couple a desired convex-concave corresponding to thedistance to the point of impact of the convex-concave portion of therotation axis on the illumination unit side with the protrusion of therotation axis on the reticle selection unit side.
 5. A dot sightingdevice comprising: a reflection mirror; an illumination having a LEDirradiating light to the reflection mirror and a transparent reticlethat is positioned in front of the LED and forms a dot image bytransmitting the light irradiated from the LED; a fixed grille formed ona lower portion of the dot sighting device, wherein the dot sightingdevice is attached to and detached from a mount for a heavy machine gunby the fixed grille; wherein the upper plate comprises a protectivewindow; a reflection mirror; and an illumination unit, and wherein thelower plate comprises: a fixed grille formed on a lower portion of thedot sighting device; a bullet path adjustment handle installed at a sidesurface of the dot sighting device; a click control bolt that connectsthe upper and lower plates and sets an origin point; a bullet pathadjustment body that is accommodated in a bullet path adjustment bodyaccommodation unit formed in the lower plate and is connected to theupper plate by fixing an end on the lower plate side of the clickcontrol bolt to an upper portion of a plate connection rotation axispenetrating a side surface of the lower plate; a bullet path adjustmentaxis that comprises a bullet path adjustment portion positioned on abullet path adjustment axis contact portion at an end of the bullet pathadjustment body, and penetrates the lower plate, thereby being connectedto the bullet path adjustment handle; a connection pin of the bulletpath adjustment body and the lower plate, penetrating the other end ofthe bullet path adjustment body and the lower plate from a side surfaceof the lower plate, thereby connecting the bullet path adjustment bodyand the lower plate; and a spring accommodation portion formed in a topsurface of the lower plate on the bullet path adjustment axis contactportion side based on the connection pin, wherein the springaccommodation portion accommodates a spring, thereby pushing the upperplate and the lower plate apart from each other, wherein the bullet pathadjustment body is rotatable around the upper/lower plate connectionrotation axis, wherein the bullet path adjustment axis contacts a topsurface of the bullet path adjustment axis contact portion of the bulletpath adjustment body, and comprises a bullet path adjustment portionhaving a plurality of contact surfaces each having a different normaldistance from the center of the bullet path adjustment axis,corresponding to a distance to a target, wherein, in the bullet pathadjustment portion, by rotating the bullet path adjustment handle, acontact surface corresponding to a distance to a desired target contactsthe bullet path adjustment axis contact portion.
 6. A dot sightingdevice comprising: a reflection mirror; an illumination having a LEDirradiating light to the reflection mirror and a transparent reticlethat is positioned in front of the LED and forms a dot image bytransmitting the light irradiated from the LED; a fixed grille formed ona lower portion of the dot sighting device, wherein the dot sightingdevice is attached to and detached from a mount for a heavy machine gunby the fixed grille; the dot sighting device further comprising areticle selection unit connected to the illumination unit, wherein thetransparent reticle is formed on a plane perpendicular to a reticlerotation axis that extends from the reticle selection unit andpenetrates the illumination unit, thus being able to rotate based on thereticle rotation axis by rotation of the reticle selection unit, and aplurality of reticles are formed on the transparent reticle on the sameradius axis around the reticle rotation axis, wherein the reticles areformed closer to the reticle rotation axis as a distance to thecorresponding point of impact is farther, and one of the reticles isselected by rotating the reticle rotation unit according to a distanceto the target wherein the reticle rotation axis comprises, around areticle rotation connection axis, a rotation axis on an illuminationunit side having a convex-concave portion with a plurality ofconvexes-concaves corresponding to a distance to a point of impact; anda rotation axis on a reticle selection unit side that has protrusionscoupled to desired convexes-concaves of the convex-concave portion on anend thereof and the other end of which is connected to the transparentreticle, wherein the rotation axis on the illumination unit side and therotation axis on the reticle selection unit side are separated from eachother by pulling the reticle selection unit, and then the reticleselection unit is rotated so as to couple a desired convex-concavecorresponding to the distance to the point of impact of theconvex-concave portion of the rotation axis on the illumination unitside with the protrusion of the rotation axis on the reticle selectionunit side.
 7. The dot sighting device of claim 1, wherein the secondsurface comprises an aspheric surface having a conic coefficient.
 8. Adot sighting device comprising: an illumination element that irradiateslight; a reflection element that reflects at least a portion of thelight irradiated by the illumination element to form an image; aconnecting element that attaches to and detaches from a mount; a firstadjustment mechanism that sets a zero point of the dot sighting device,the first adjustment mechanism including a first control mechanism thatadjusts a zero point in upper and lower directions; and a secondadjustment mechanism that selects a bullet path, the second adjustmentmechanism being distinct from the first adjustment mechanism, whereinthe reflection element is coupled to a first plate, the connectingelement is connected to a second plate, and the second adjustmentmechanism adjusts a slope of the first plate relative to the secondplate.
 9. The dot sighting device of claim 8, wherein the secondadjustment mechanism is connected to the first adjustment mechanism toselect the bullet path in a state in which the zero point is set. 10.The dot sighting device of claim 8, wherein the first adjustmentmechanism includes a second control mechanism that adjusts the zeropoint in left and right directions.
 11. The dot sighting device of claim8, wherein the second adjustment mechanism adjusts a slope of thereflection element relative to the connecting element.
 12. The dotsighting device of claim 8, wherein the second adjustment mechanismincludes a plurality of selections, each selection corresponding with apredetermined bullet path adjustment associated with a selected distanceto a target.
 13. The dot sighting device of claim 8, wherein the secondadjustment mechanism includes a plurality of slope selection portionsthat, when selected, set a slope of the first plate relative to thesecond plate corresponding to a predetermined distance to a target.